Single-roll crusher



W. K. LIGGETT.

SINGLE ROLL CRUSHER. APPLICATION FILED JULY 10. (916.

1,339,932. Patented May 11,1920.

2 SHEETS-SHEET 2.

INVENTOR A 170E5 5 y STATES PATENT OFFICE.

WILLIAM K. LIGGETT, F COLUMBUS, OHIO, ASSIGN'OR TO THE JEFFREY MANUFAC- TUBING COMPANY, OF COLUMBUS, OHIO.

SIN GLE-ROLL CRUSHER.

Specification of Letters Patent.

Patented May 11, 1920.

Application filed July 10, 1916. Serial No. 108,485.

To all whom t may concern:

Be it known that I, WILLIAM K. Lrcen'r'r,

' a citizen'of the United States, residing at heretofore manufactured have been ad justed to produce the desired fineness of product, their capacity has usually been reducedbeyond the limit of profitable operation and an unduly large portion of the coal has been reduced to dust.

The common expedient by which these difiiculties are avoided is the use of two crushing machines, one adapted to crush large lumps to a comparatively small size being placed over a second machine which is adapted to reduce the product of the first machine to the size required. Such a double machine is necessarily expensive and requires a relatively powerful driving mechanism. In the patent to l/Vhiting, No. 1,045,7 63, is disclosed a machine comprising a roll rotating adjacent a stationary breaker plate wherein the surface of the roll is thickly set with large number of relatively small crushing teeth and a much smaller number of relatively long hookshaped teeth, the hook shaped teeth serving to draw the larger fragments of the coal down into the machine to be crushed, and the small crushing teeth to crush it to the desired size. A smooth breaker plate is normally supported in such manner that there shall be only a running clearance between its lower part and the tops of the crusher teeth. In order that the longer hook-shaped teeth may pass, grooves are provided in the breaker plate, and the proportions 'of the teeth and grooves are such that there shall be only the necessary running clearance and the grooves shall be no wider than the greatest desired dimension of the fragments of coal in'the product. By this arrangement of parts the throat through which the coal passes affords no opening through which fragments larger than the desired, limit may pass. Such machines have proven satlsfactory within certain limits of operation, but when it has been desired to reduce the fineness of the product below a certain maximum, three quarters of an inch say, the capacity of the machines has been reduced beyond the limits of profitable operation.

It is the principal object of this invention to provide a machine of relatively large capacity, which shall be adapted to take run of mine coal, including both large and small fragments, and, by a single operation, reduce it uniformly to the small size suitable for modern automatic stoking furnaces.

A further object is to produce a machine of simple design and great strength in which the parts subjected to the greatest wear may be readily and conveniently renewed.

Other objects will appear in the following specification, wherein is set forth the preferred embodiment of my invention, reference being had to the accompanying drawings of which Figure 1 is a general plan view of a machine embodying my invention.

Fig. 2 is an end elevation of the machine shown in Fig. 1.

Fig. 3 is a cross section taken along the line 3-3 of Fig. 1.

Fig. i is a perspective view of one of the renewable segments of the crushing roll.

Fig. 5 is a fragmentary longitudinal section of the crushing roll showing particu larly the method of inserting the renewable teeth.

Fig. 6 is a perspective view of the breaker plate.

Referring to the drawings, the reference character 1 represents the end frames upon which the crushing mechanism .is mounted. Journal bearings 2 and 3 are provided in these end frames in which are mounted the roll shaft 4 and the countershaft 5. These journal bearings are provided with the usual removable caps so that the machine may be easily taken apart when so desired. A hub 6 provided with radial wings 7 is keyed to one end of the shaft 5, and in turn is fastened to a pulley wheel 8 by means of pins 9 passing through the wings 7 and the arm of the pulley 8. These pins 9 are made of some such material as wood, and their cross portion of the roll.

Or I l a size appropriate have attached to the segmental plates section is such that in case of a sudden overload being thrown upon the machine, they will shear, thus disconnecting the counter shaft from the driving element. This provides a safety device such as will eliminate any possible danger of the machine being demolished or the bearings injured, due to sudden and unexpected overloads.

Mounted on theshaft 1 is a drum or roll 10- around the periphery of which is arranged a series of segmental plates 11 which are formed on their outer surfaces with elongated sharp-edged ribs 12 extending parallel to the axis of the roll. Preferably the front sides of the ribs are approximately radial to the axis of the roll. As will later appear, the ribs cooperate with other parts in the crushing of the coal and the radial and circumferential dimensions of the ribs bear a definite relation to the desired size of the product. 7

It has been found that when such a crushing roll is provided only with ribs of I to the production of finely crushed coal, that the larger lumps will roll upon the top of the crushing roll and not be drawn down into the machine to be crushed. To overcome'this difficulty .1 1 narrow, radially elongated teeth 13 adapted to engage these large fragments of coal and drag them into the machine to be crushed. These teeth are formed with tapering sides and a relatively broad base 1% and closely fit into apertures 15 formed at spaced intervals in the segmental plates 11. Formed in the segmental plates 11 are apertures 16 through which pass radialbolts 16 by which the said plates are held in place. When these plates are drawn down to place the broad bases 14 of the teeth 13 are pressed against the roll 10 which looks them securely to place. he roll 10 is driven by a gear 17 mounted on the end of the shaft 1 opposite to the end of the machine on which the pulley wheel 8 is mounted. A pinion 18 is mounted on the counter shaft 5 opposite to that on which the hub 6 is keyed and en gages the gear 17 thereby furnishing driving means for thecrushing roll.

Attached to the frame members 1 are re movable end plates .19 and a rear cover plate 20 which serve to inclose the upper his construction provides removable plates which, when in place, seal the chamber within which the roll operates, thereby preventing the escape of dust, and also, because of their easy removal, allowing access to the bolts 16 so that the segmental section 11 may be removed or replaced without the entire dismantling of the machine. A hopper 21 is attached to the upper edge of these plates and through this hopper is introduced the coal to be' crushed.

A breaker plate 22 is pivoted on the shaft 23 at the upper front side of the machine, being disposed so that it and the roll form opposite, downwardly converging walls of a passage through which the coal moves to the final crushing points at the lower side of the plate. Said plate is provided at its lower side with a plurality of removable shoes 24 arranged transversely of that part of the breaker plate which is adjacent the crusher roll, and so spaced apart from each other as to form slots 25lthrough whichthe long hook-shaped teeth 13 may pass. These shoes 2st are beveled on their upper and lower edges so as to engage with the clamping surfaces 26 and 27 formed on the breaker plate and the clamping plates 28 respectively. These clamping plates 28 are at tached to the lower edge of the breaker plate 22 by the clamping bolts 29 by which they are pressed against the removable shoes 24; to lock them securely in place, lhe surfaces of the shoes 21 opposed to the crush ing roll are formed with elongated sharpedged ribs 30." These ribs are disposed in 7 planes at right angles to the'ribs 12 on the roll and extended closely adjacent to the last named ribs, the two sets of ribs cooperating in a peculiar manner, as the roll turns, to crush the coal to a uniform size. As in the case of the ribs of the roll, the dimensions of the ribs 30 bear a definite relation to the size of the product.

An arcuate slot 31 is formed intermediate the ends of the breaker plate and has pass ing through it a rod 32 the outer ends of which are mounted in the end frames 1. This provides a stop as well as a guide when the breaker plate swings about the shaft 23. A shaft 33 extends through the breaker plate below the arcuate slot 31 and has mounted upon its endstwo eye bolts 34 which extend rearwardly through the lugs upon the frame members 1. Springs 36 are placed upon the extremities of the eye bolts 34 outside the lugs and are retained in place by the nuts 37 by the adjustment of which the tension of the springs 36 may be regulated. This provides a cushioning of the breaker plate so that when an unusually hard piece of material is passed between the roll and the breaker plate, instead of breaking the teeth on the roll or jamming the machinathe breaker plate will be swung back as far as necessary,

depending upon the tension placed upon the springs 36.

In operation machines of this character are commonly arranged to receive the coal which is to be crushed in relatively large masses. The hopper 21 is often so located as to receive the coal from drop bottom cars or from large grab buckets or by other rapid methods of handling. In such cases there will often be a load of several tons of coal directly upon the crushing roll. As the roll revolves, the teeth 13 will engage the fragments of coal lying directly in front of the plate 38 of the hopper 21, carrying a ribbon of coal forward and downward through the space between the breaker plate and the crushing roll. As one fragment moves forward another slides down the hopper plate 38 to take its place and in this way the coal from the rear side of the hopper is carried down into the machine, that at the forward side remaining stationary until the balance is out of the way when it will slide down the plate 89 of the hopper and over the breaker plate as a chute to pass through the machine. It is to be observed that the teeth 13, in feeding the coal over the roll and downward between the same and the breaker plate, perform the additional function of partially crushing the larger blocks of the coal; for, as will readily be understood, the action of the teeth upon said larger blocks is to dash them with great force against the breaker plate 22 and a partial crushing of the larger blocks results so that the resultant mass is in condition to be forced farther downward between the converging walls formed by the roll and the breaker plate. Of course, the saw toothed sectional form of the ribs12 gives them a feeding action on the small particles of coal but the ribs are not large enough to effelctively engage the larger blocks of the coa In the downward movement of the coal through the machine, it comes to the final crushing points between the ribs of the roll and the ribs on the shoes 24 of the breaker plate. The action of the two sets of ribs or.- the coal is peculiar; the ribs, disposed as they are at right angles-to each other, tend to divide the ribbon of coal along lines at right angles to each other, cutting the coal into fragments of a general cubical form rather than indiscriminately mashing it. Hence, while the crushing action of the ribs is exceedinglyeifective, there is much less tendency to reduce much of the coal to dust than there is in the case of prior machines in which the roll is formed with iso lated teeth working on a relatively plain or smooth faced breaker plate. It will be understood that the ribs both on the roll and on the breaker plate are spaced apart a distance approximately equal to the maximum permissible dimensions of the fragments of the product, and since, when the machine is adjusted for fine crushing, there is no space for larger fragments to pass through, the fineness of the product is assured. Furthermore, the cooperative action of the two sets of ribs is such that while there is a relatively slight tendency to reduce the coal to dust, and while the crushing action is remarkably tinuously the full length of the roll, but

in referring to the ribs both of the roll and of the breaker plate as elongated, I intend simply to distinguish them from isolated teeth such as have been used on the crushing rolls of prior machines and by the term elongated mean to indicate that the working edges of the ribs are elongated to a length greater than the distance between the ribs on the opposing element of the crusher.

It is to be understood that cooperating sets of crusher ribs, such as are herein set forth, may be utilized in forms of construction differing more or less radically in some respects from the structure herein disclosed, and in my two co-pending applications of even date herewith and bearing the Serial Nos. 108,486 and 108,487 respectively, I have shown two other forms of construction in which such ribs are embodied. In the present application I do not claim broadly such co-acting crushing ribs as this subject-matter is broadly claimed in my copending application Serial No. 108,486, above referred to.

What I claim is:

In an apparatus for crushing coal, the combination of a frame, a crushing roll rotatably mounted in the frame, a breaker plate mounted in the frame at one side of the roll, said roll and breaker plate forming opposite downwardly converging walls between which the coal passes downwardly to the final crushing points, uniformly spaced longitudinally extending sharp edged ribs formed upon the surface of the roll, feeding teeth extending radially from the surface of the roll to engage the material to be crushed and draw it downwardly into the tapering passage, a transverse series of breaker shoes detachably secured to the breaker plate to form a continuation of its working surface, said breaker shoes being spaced apart to form slots to permit the passage of the feeder teeth of the roll, uniformly spaced sharp edged ribs formed upon the surface of the breaker shoes extending at right angles to and closely approaching the ribs of the roll to cooperate therewith to accurately size the crushed coal.

In testimony whereof I afiix my signature in presence of two witnesses.

WILLIAM K. LIGGETT.

Witnesses:

HARRY C. DEAN, DUDLEY T. FISHER. 

